Combat veterans are at an increased risk for the development of posttraumatic stress disorder (PTSD) and marital discord. Although a number of investigations have independently linked both PTSD and marital conflict to risk of cardiovascular disease, the leading cause of death in the United States, their combined influence has not yet been examined within the context of a military population. Stress associated with marital interactions could be a pathway through which PTSD influences disease risk; however this has yet to be addressed. The proposed investigation is an initial test of this possible mechanism linking PTSD, marital strain, and risk of cardiovascular disease. Specifically, it will assess the association of PTSD and cardiovascular reactivity (CVR; i.e., increases in heart rate and blood pressure) during potentially stressful marital interactions. We will examine CVR in both veterans (with and without PTSD) and their spouses, as well the recovery of these cardiovascular stress responses following potentially conflictual marital interactions. These relations will be tested via several specific aims. The primary aim of the proposed investigation is to evaluate the differential physiological impact of negative marital interactions on Operations Enduring and Iraqi Freedom veterans, with and without PTSD, and their spouses. This investigation will primarily focus on CVR, specifically changes in heart rate and blood pressure. Although prior studies have linked PTSD to CVR to stress in veterans, there has been no prior research on these responses during marital interaction and no prior studies of the physiological impact that combat-related PTSD may have on spouses of these individuals. We will also evaluate possible physiological determinants of these cardiovascular responses, using impedance cardiography methodology. We will further explore relationship quality as a mediator of the association between PTSD and physiological reactivity to stress. Lastly, we will examine potentially modifiable aspects of negative marital interactions that may relate to physiological reactivity, such as anger and anxiety in veterans and their spouses. Research of this type is necessary to understand more completely the mechanisms by which combat-related PTSD relates to morbidity and mortality. Findings from this investigation may help to refine interventions for couples with combat-related PTSD, with the ultimate goal of reducing the risk for cardiovascular disease in this population. The objectives of this investigation fit cleanly into the National Institutes of Health mission to extend healthy life and reduce the burden of illness and disability and may ultimately improve the lives of our nation's military service members and their families. These goals aim to be accomplished within the context of a specific research training program focused on developing expertise in the areas of psychophysiology, including physiological reactivity to stress, dyadic relationships, and the military population. The training plan proposed includes completion of a number of specific courses, laboratory trainings, close supervision, mentoring, scientific writing and presentation experience, and workshop attendance. PUBLIC HEALTH RELEVANCE: Up to 25% of service members deployed to Iraq and Afghanistan return home showing signs of Posttraumatic Stress Disorder (PTSD) and a large portion of these veterans exhibit related medical and marital difficulties. Findings from this investigation will give us a better understanding of military couples' physiological responses to marital stress and may ultimately help to refine interventions for couples with combat-related PTSD, with the ultimate goal of reducing the risk for cardiovascular disease in this population. Such improvements may more broadly reduce the health care utilization and national costs of treating service members with PTSD and will increase our ability to thoroughly care for spouses of our nation's veterans.